Loose fill packing elements have evolved over the years for insulating articles transported in shipping containers such as cardboard cartons against vibration and impact.
Fragile articles have been packaged in cardboard containers such as boxes and cartons using loose fill packaging material of various forms. Such fill as shredded paper, excelsior or straw padding has in the past provided a shock absorbing cushion. Fill elements having the property of resilience and light weight include popped corn which is the subject of U.S. Pat. No. 2,649,958. U.S. Pat. No. 3,074,543 describes fill material constituting tiny collapsible cylinders such as waste or cut straw stock.
Expanded plastic foam has been found to be particularly suited for use as fill material since the foam has good shock absorbing characteristics, is lightweight, resists crushing and has a high volume of cells or void spaces ranging from 25% to 85% of the total volume of the loose fill elements.
U.S. Pat. No. 3,896,934 discloses foam plastic packing elements, originally of cylindrical or annular shape which are expanded and curled to form a hollow configuration of a form which when viewed in side elevation, resembles a fleur de lis and when viewed from an end, takes the configuration of a greek letter .theta. or the number 9.
U.S. Pat. No. 4,166,875 discloses loose fill packing elements which are free flowing, formed of styrofoam, non-nesting and non-interlocking and of block form having a base or body portion and three leg portions extending substantially from the body portion and defining recesses between the leg portions, with the leg portions having a width in excess of the width of the recess. The block may take the form of the letter W.
Companion U.S. Pat. No. 4,169,179 discloses such loose fill packaging elements of U-shaped configuration, whose bottom of the base portion has longitudinally extending slits at laterally spaced position to provide a spring-like construction to the two legged portions thereof.
U.S. Pat. No. 4,514,453 discloses loose fill packing elements formed of resilient foam thermoplastic material such as polystyrene or polyethylene which elements are of generally S-shaped configuration such that the elements abut each other without interlocking.
U.S. Pat. No. 3,650,877 teaches the formation of a resilient cushioning dunnage element of helical coil-like configuration by crumpling a web of paper into a relatively narrow strip and pressure forming the strip into helical form.
In today's world, where man is continuing to pollute the environment, the polystyrene fill elements not only represents significant volume, but upon the package arrival, such elements must be disposed of. While they are reusable conventionally they are thrown away. Waste management represents a significant problem to this country, and to the world. Existing landfills capable of receiving the styrofoam packaging element are being rapidly filled with our day-to-day garbage and other waste. Importantly, the styrofoam fill elements do not break down when thrown away and due to their high volume, and they take up considerable space which cannot be reused.
The Applicant, in early 1989, conceived of packaging elements formed of recycled newspaper, mass produced by a vacuum molding process from a liquid slurry of water and chopped newspaper, identical to the material making up egg cartons as a replacement for plastic foam elements wholly of cellulose, in the form of hand-pressed cup-shaped pellets.
It is, therefore, a primary object of this invention to provide improved loose fill packaging elements of cellulose fibers, of recycled, shredded newspaper, trimmings from newsprint and envelopes, which may be readily manufactured by molding a slurry formed solely of cellulose and water, in a vacuum mold into thin hollow walled shells which include molded in structural elements to provide localized rigidity, which may be of hemispheric, oblong, truncated cone or polygonal shape, which are non-nesting, lightweight, energy absorbing and which inherently provide structural cushioning or elasticity to duplicate the sponginess of the prior solid styrofoam peanuts.